title: Prevalence and risk factors for pulmonary arterial hypertension in a large group of β-thalassemia patients using right heart catheterization: a Webthal study.
abstract: BACKGROUND
  Pulmonary arterial hypertension (PAH) remains a concern in patients with β-thalassemia major (TM) and intermedia (TI); however, studies evaluating its prevalence and risk factors using systematic confirmation on right heart catheterization are lacking.
  
  
  RESULTS
  This was a multicenter cross-sectional study of 1309 Italian β-thalassemia patients (mean age 36.4±9.3 years; 46% men; 74.6% TM, 25.4% TI). Patients with a tricuspid-valve regurgitant jet velocity ≥3.2 m/s (3.6%) on transthoracic echocardiography further underwent right heart catheterization to confirm the diagnosis of PAH (mean pulmonary arterial pressure ≥25 mm Hg and pulmonary capillary wedge pressure ≤15mm Hg). The confirmed PAH prevalence on right heart catheterization was 2.1% (95% confidence interval [CI], 1.4-3.0) and was higher in TI (4.8%; 95% CI, 3.0-7.7) than TM (1.1%; 95% CI, 0.6-2.0). The positive predictive value for the tricuspid-valve regurgitant jet velocity ≥3.2 m/s threshold for the diagnosis of pulmonary hypertension was 93.9%. Considerable functional limitation and decrease in the 6-minute walk distance were noted in patients with confirmed PAH. On multivariate logistic regression analysis, independent risk factors for confirmed PAH were age (odds ratio, 1.102 per 1-year increase; 95% CI, 1.06-1.15) and splenectomy (odds ratio, 9.31; 95% CI, 2.57-33.7).
  
  
  CONCLUSIONS
  The prevalence of PAH in β-thalassemia patients as confirmed on right heart catheterization was 2.1%, with an ≈5-fold higher prevalence in TI than TM. Advanced age and splenectomy are risk factors for PAH in this patient population.
  
  
  BACKGROUND
  http://www.ClinicalTrials.gov. Unique identifier: NCT01496963.
authors.affiliation: Galliera Hospital, Genoa, Italy (G.D., V.P., G.L.F.); University of Cagliari, Cagliari, Italy (R.G., P.B., M.-E.L.); IRCCS Ca' Granda Foundation Maggiore Policlinico Hospital, University of Milan, Milan, Italy (M.D.C., K.M.M.); University of Turin, Turin, Italy (A.P.); Perrino Hospital, Brindisi, Italy (A.Q.); S. Francesco Hospital, Nuoro, Italy (G.C.); and Seconda University, Naples, Italy (S.P.).
authors.forename: Giorgio
authors.initials: G
authors.lastname: Derchi
authors.forename: Renzo
authors.initials: R
authors.lastname: Galanello
authors.forename: Patrizio
authors.initials: P
authors.lastname: Bina
authors.forename: Maria Domenica
authors.initials: MD
authors.lastname: Cappellini
authors.forename: Antonio
authors.initials: A
authors.lastname: Piga
authors.forename: Maria-Eliana
authors.initials: ME
authors.lastname: Lai
authors.forename: Antonella
authors.initials: A
authors.lastname: Quarta
authors.forename: Gavino
authors.initials: G
authors.lastname: Casu
authors.forename: Silverio
authors.initials: S
authors.lastname: Perrotta
authors.forename: Valeria
authors.initials: V
authors.lastname: Pinto
authors.forename: Khaled M
authors.initials: KM
authors.lastname: Musallam
authors.forename: Gian Luca
authors.initials: GL
authors.lastname: Forni
mesh_terms: D000328:Adult; D006328:Cardiac Catheterization; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D004452:Echocardiography; D065627:Familial Primary Pulmonary Hypertension; D005260:Female; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis* / Q000453:epidemiology*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D011237:Predictive Value of Tests; D015995:Prevalence; D011669:Pulmonary Wedge Pressure; D012307:Risk Factors; D017086:beta-Thalassemia / Q000453:epidemiology*
keywords: catheterization; echocardiography; pulmonary arterial hypertension; risk factors